Property, plant and equipment (Tables)

3 Months Ended

Mar. 31, 2023

Property, plant and equipment

Schedule of elements of property, plant and equipment

	March 31,		December 31,		Estimated
	2023		2022		Lives
(in thousands)	(unaudited)
Property, plant and equipment
- Land	$	1,255	$	1,255
- Land improvements		319		319	6-10 years
- Buildings		1,446		1,446	25-39 years
- Building improvements		3,422		3,396	25-39 years
- Cylinders		13,309		13,315	15-30 years
- Equipment		27,675		27,258	3-10 years
- Equipment under capital lease		315		315	5-7 years
- Vehicles		1,773		1,773	3-5 years
- Lab and computer equipment, software		3,215		3,103	2-8 years
- Furniture & fixtures		926		840	5-10 years
- Leasehold improvements		852		852	3-5 years
- Construction-in-progress		3,310		3,533
Subtotal		57,817		57,405
Less: Accumulated depreciation		(37,588)		(36,837)
Total	$	20,229	$	20,568